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427 knocking

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Old 09-12-2012 | 01:15 PM
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Default 427 knocking

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I have a 427 and missed 3rd and over revved it and a few weeks later it started knocking. Had to replace the valve train and lifters on the passenger side. Once I had everything replaced it is still making a knocking sound that sounds like it's coming maybe from the cam? I'm not a mechanic and I've had a lot of different story's on what is wrong. Just looking for some other opinions.
Old 09-12-2012 | 01:20 PM
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If you over revved it, there's a possibility that it's a bent pushrod. You said that you replaced the valve train on the passenger side, is the "knock" coming from the driver's side now?

Last edited by KevinR; 09-13-2012 at 04:12 PM.
Old 09-12-2012 | 01:27 PM
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No it's coming from the center of the engine and none of the push rods look bent. I've laid them side by side and rolled them all no wobble or anything.
Old 09-12-2012 | 01:29 PM
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Not trying to be an *** here, but why did you only change the passenger side lifters? Also, what is your set up?
Old 09-12-2012 | 02:24 PM
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Just financial reasons. And I didn't see any problems with the other lifters. You thinking its a lifter problem? And it's just a regular 427 set up with a fast 92 intake no other mods to the motor.
Old 09-12-2012 | 02:32 PM
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Just financial reasons. And I didn't see any problems with the other lifters. You thinking its a lifter problem? And it's just a regular 427 set up with a fast 92 intake no other mods to the motor.
Old 09-12-2012 | 04:05 PM
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Originally Posted by Arondwreck12
Just financial reasons. And I didn't see any problems with the other lifters. You thinking its a lifter problem? And it's just a regular 427 set up with a fast 92 intake no other mods to the motor.
It's hard to say. Can you post a video of it?
Old 09-13-2012 | 11:45 AM
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If you over-revved it, you might have spun a bearing and have a rod knocking. If you continue to run it without inspecting the bottom end, you can kiss that engine goodbye,
Old 09-14-2012 | 04:07 PM
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Drain the oil into a clean container and inspect for any signs of copper bearing material.
Perform a leak-down test on all cylinders which will tell you if you have a bent valve

By the way, where are you located?
Old 09-14-2012 | 09:08 PM
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Crazy idea, but exhaust leaks can sound like "knocking" sometimes



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